Thread-gripping device



F. E. BERTRAND.

THREAD GRIPPING DEVICE.

APPLICATION FILED JUNEH 1917- 1,369,773. Patented Mar. 1,1921.

2 SHEETS-SHEET l. 1

F. E. BERTRAND.

THREAD GRIPPING DEVICE.

' APPLICATION man :uuaa, 1912 I 1,369,773. PatentedMar. 1, 1921. V 2 ssss T S-SHEET z.

d 52 1 Q E 3 95 Inven for: @19 X W 5W0! I I UNITED STATES PATENT orr cs.

FREDERIG IBE ETRAND, OF LYNN, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO "UNITED SHOE MACHINERY CORPORATION, OF PATEBSON, NEW J I A CORPORATION OF NEW JERSEY.-

' THREAD-GRIPPING DEVICE.

To all whom it may concern Be it known that I, Fnnonnro E. BER- TRAND, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented certain new' and useful Improvements in Thread-Gripping Devices; and I do herebydeclare the following to be a full, clear, and exact description of'the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to wax-thread sewlng machmes, and 7 more particularly to thread grlpplng devlces for holdlng the free end' of the thread during the first part of-theseam formation.

In the'thread gripping'devices ordinarily applied to wax-thread sewing machines, the jaws of the gripping device are not opened to release the thread during the formation of the first part of a seam, but the thread is drawn from between the gripping jaws by the feeding movement of the work. The friction of the thread as it is being drawn from between the; gripping jaws tends to retard the feeding of the work, and to displace the work relatively to the stitch forming devices, and may impose considerable strain on the work feeding devices.

The objects of the present invention are to improve the construction and mode of operation of thread gripping devices ofthis class for wax-thread sewing machines, and to produce a thread gripping device inwhich the objectionabove pointedout is obviated.

Wax-thread sewing machines are ordinarily provided with a friction clutch for driving the main shaft of the machine from.

the power shaft, the engagement of which is controlled by a manually operable member such as a treadle. In starting the machine the operator first depresses the treadle with a comparatively light pressure to bring the members of the driving clutch initially into engagement, and then gradually increases the pressure on the treadle. The members of theclutch are thus initially engaged with a light pressure, allowing considerable slip between the clutch-members, and the machine is started at a relatively slow speed and without'subjecting the parts to excesslve strain. The gradual increase in the pressure on the treadle and the resultant increase in the pressure with which the clutch members are held, together is continued until the Specification of Letters Patent. Patented Mar; LIQZL Application filed-Tune 8, 1917. SeriaI No.'173,554.

clutch members are firmly engaged, so that I there is practically no slip between them, and

the jaws of the gripping device by the move ment of the operatorin continuing the move? -ment of said member to, engage firmly the members of the clutch. With this construction the'jaws of the grippingdevice will be; closed during the formation of at least one stitch of the seam, and will then be opened to release the thread. The invention, however, is not limited to the particular construction and arrangement of parts de-. scribed as constituting the above feature, and embodies other features .hereinafter "described andpointed out in the claims,

The invention will be readily understood from the accompanying drawings illustrating a machine embodying the invention in its preferred form, and the following detailed description of the constructions there in shown. i g

In the drawings, Figure 1 is a; view, in front elevatiorn'of a portion of the head of a wax-thread shoe sewing machine embodying the invention; Fig; 2 is aview, in side elevation, partly in section, of a portion of the head ofthe machine; Fig. 3 is a detail view, in front elevation, illustrating the drlvmg mechanism for the machine and certain parts of the thread grlpping mecha-U nlsm; Fig. 4: 1sa v1ew,1n side elevation,

partly in section, illustrating certain of the r I parts shown in Fig. 3; 5 is-a detail under side plan view illustrating the upper thread gripping jaw; Fig. 6 isa detail view,

in side elevation, illustrating the upper thread grippingj aw; Fig. 7 is a view, in side elevation, illustrating the lower thread grip ping jaw; and Fig. 8 is a detail under side the insoles of welted shoes without first as- I sembling the parts upon a last, and has the same general construction, arrangement and mode of operation as the machine illus trated and described in applicants pending application Serial 373,390, filed April 12, 1920. The machine comprises a curved hook needle 2, a curved work-feeding awl 4,

f a looper 6, a shuttle 8', a take-up 10, a tension aredriven from a series of cams mounted on the main shaft 24. A pulley 26 is mounted wheel 12, and certain other devices co6perat= ing with these parts to form a lockstitch seam. The machine also comprises a channel guide or work support 14 arranged to engage in the channel of an insole, a member 16 arranged to embrace the marginal portion of an insole and constructed to form a sole guide 18 for engaging the inner face of the marginal portion of the insole,

and a shoulderguide 20 for engaging with the shoulder of the insole, and a presser-foot 22 arrangedto engage the'outer face of the marginal portion'of the upper. All of the parts of the machine briefly referred to above have substantially the same construction, arrangement and mode of operation as the corresponding parts of the machine illustrated and described in applicants endin a) lication referred toabove and, b 7

reference may be had tosaid application for afull and complete description of the'same. All of the operating parts of the machine upon one end of the main shaft 24 and is grooved to receive a driving belt. The pulley 26 is driven from a driving pulley 28 loosely mounted upon a driving shaft 30 by means of a driving belt (not shown), passing about the pulley 28 and about the pulley 26. The driving shaft 30 is mounted in bearings in the standards 31 and 32 and carries a disk 34 fixed thereto which constitutes -one member of a friction driving clutch. The other member of the clutch, in- V dicated at 36, is mounted upon the driving pulley 28.' The pulley 28, in addition to being loosely mounted on the shaft 30, is slidable longitudinally of the shaft to engage the member 36 of the friction clutch withthe cooperating clutch member 34. The pulley 28is provided with a hub 38 formed with a groove 40,'in whichengage rolls 42 -mounted on the forked upper end of an arm 44 embracing the hub 38. The arm 44 is fixed to a rock shaft 46 mounted in bearings in standards 48. The arm 44 is acted upon by a coiled spring 49 which tends to swing the arm in a direction to disengage the clutch member 36 from the clutch member.

34. The movement of the arm 44 and the pulley 38 underthe action of the spring 49 is limited by the engagement of the hub of the pulley with a collar 50 fixed to the shaft 30. To the shaft 46 is also secured laterally extending treadle arm 51 terminating in a relatively broad plate 52 to receive the foot of the operator. With this construc tion, by the depression of the treadle arm 51 the rock shaft 46 is turned in its bearings, and the arm 44 is swung to the right I (Fig.3) to. carry the clutch member 36 into engagement with the cofiperating clutch member 34. U

The thread gripping device for gripping the free ends of the thread comprislng a the forward face of the groove when the gripping jaws are closed. The jaw- 60 terminates in a knife edge 65, across which the threads, after being inserted between the gripping jaws, are drawn to sever the The member 54 is secured in fixed position upon the machine by means of a screw 66 passing through an opening 68 in,

said member, and threaded into the frame. The member 54 is held from turning on the screw by means of a pin 70 engaging in a slot 72 in said member. ber 58 is secured by screws 73 to the upper end of an arm 74 formed on a lever 76 pivoted upon a stud 78. The lever 76 is acted upon by a spring 80 coiled about a boss 82 formed on the lever and having one end en- The movable mem-.

gaged in an opening 84 in the frame and V the other arm engaged beneath the lever 76. This spring tends to maintain the lever 76 in elevated position with the thread gripping jaws in closed relation. The lever 76 is formed with a second arm 86 to which is 7 connected the upper end of a rod 88, the

lower end of which is connected with a treadle lever 90 pivoted at 92 on the frame of the machine. Upon the forward end of the lever 90 is mounted a stud 93, the head of which is arranged to project into an opening 94 in the plate 52. The downward movement of the treadle lever 90 is limited by the engagement of an adjustable abutment screw 96 secured in the lever with the contact face 98 onthe base of the machine frame. The treadle lever 90 is formed with a projection extending beyond the treadle 52, which the operator may engage with'his foot to depress the treadle lever 90 independently of the treadle 52.

The thread gripping device is shown in Fig. 1 with the jaws thereof in closed positions. After the machine is stopped at the completion of the sewing of a seam, the treadle 52 then being released, the operator in removing the work from the machine, de-

presses the treadlelever 90 to open the jaws of the gripping device, inserts the needle thread, and also, if desired, the shuttle thread, between the jaws, releases the treadle lever 90 to allow the gripping jaws to close' on the threads, and draws them across the knife edge to sever the same. When the treadle 52 is released, the position of the same is determined by the engagement of the hub of the pulley 28 with the stop collar 50, and the position of the upper end of the stud 93 is determined by the upper limiting or closed position of the gripping jaw 60. The parts are'constructed and arranged so that when the treadle 52 is released the upper face of said treadle assumes a limiting position some distance above the upper end of the stud 93, asshown in Fig. 1. This distance is at least such as to allow the treadle 52 to be depressed by the foot of the operator to engage initially or lightly the clutch member 36 with the clutch member 34 to start the machine before the operators foot engages the upper end of the stud '93,'and

is preferably somewhat in excess of the distance required to allow for such movement of the treadle. With this construction, as the operator depresses the treadle 52 to engage lightly the members of the driving clutch to start the machine at relatively slow speed, the jaws of the thread gripping device will remain closed so as to holdsecurely the free ends of the threads. As the operator, after the initial engagement of the clutch members, gradually increases the pressure of his foot on the treadle 52, the said treadle is depressed farther, owing to the resiliency of the parts, and the foot of the operator engages the upper end of the stud 93 and depresses the same, thereby actuating the treadle lever 90, the mass, and the lever 76 to open the jaws of the gripping device to release the thread. The operator depressesvthe treadle 52 in such a manner as to start the machine and cause the main shaft to make at least one revolution before the stud 93 is depressed to open the thread gripping jaws. The free ends of the thread will thus be held by the thread gripping device during the first cycle of operations, thereby insuring the proper formation of the first stitch. After at least the first stitch is set in the work, the treadle 52 is depressed farther so that the operators foot is engaged with the stud 93 to depress the same to open the thread gripping jaws. The operator may continue the light pressure upon the treadle 52 to hold the members of the driving clutch lightly in engagement for more than the first cycle of operations if he prefers. The setting of the first stitch in the work, however, ordinarily will hold the free ends of the threads so that the threads may then be released by the thread gripping device. The depressing movement is imgagement of the clutch.

'ment of parted to the stud 93 to open the thread gripping jaws to release the threads before the work has been fed far enough to drawthe threads taut between the gripping device-and the work.

Having explained the nature of the inven-' tion, and having specifically described a machine embodyingthe same in its'preferred form, what is claimed is: 1. A wax-thread sewing machine, having, in combination, stitch forming devices, a main'shaft from which said-devices are op-' erated, a friction clutch for driving. the

shaft, a manually operable member, and connections for controlling the engagement and 0 disengagement of the clutch, a thread gripping device comprising relatively movable thread gripping jaws, and means arranged, to, be operated to open the gripping aws by the movement of the operator in moving said member in a directionto cause the en'- 2. A wax-thread sewing machine, having, in combination, stitch forming devices, a main shaft fromwhich said devices are operated, driving mechanism for the shaft, a manually operable member, and connections for controlling the connection of'the driving mechanism with and the disconnection of saidmechanism from the shaft, a thread gripping device for holding the 'free end of the thread at the beginning of a seam foring mechanism with and the disconnection of said mechanism from the shaft, a thread gripping device comprising relatively movable thread gripping jaws, and means for moving relatively the jaws of the gripping device arranged to be actuated to open the I I gripping jaws by the movement of the operator in moving said member in a direction to cause the connection of the driving mechanism with the shaft. v t

4:. A wax-thread sewing machine, having, 1 0 incombination, stitch forming. devices, a main shaft from which said devices are op erated, driving mechanism for the shaft, a manually operable member and. connecv tions for controlling the 'connectionof the driving mechanism with and thedisconnection of said mechanism from the shaft, a: thread; gripping device comprising relatively movable thread gripping jaws, and means for moving relatively the jaws of the gripping device arranged to remain inactive during the initial movement of said member in a direction to cause the connec tion of the driving mechanism with the gripping device comprising relatively movable thread gripping jaws, and'means arranged to be actuated to open the gripping jaws by the movement of the operator in moving said member in a direction to cause the connection of the driving mechanism with the shaft and to close the jaws as said member is released by the operator to cause the disconnection of the driving mechanism from the shaft. 7

6. A wax-thread sewing machine, having, in combination, stitch I forming devices, a main shaft from which said devices are operated, driving mechanism for the shaft, means for connecting the driving mechanism with and for disconnecting said mechanism from the shaft, a thread gripping device comprising relatively movable thread gripping jaws, and mechanism'for moving relatively the jaws of the gripping device constructed and arranged relatively to said means to be actuated to open the jaws. upon the actuation of saidmeans to connect the driving mechanism with the shaft. 7 A wax-thread sewing machine, hav ing, in combination, stitch forming devices,

7 a main shaft by which said devices are 0perated, driving mechanism for the shaft, means for connecting the driving me-chanism with and for disconnecting saidmechanism from the shaft, a thread gripping device comprising relatively movable thread gripping jaws, and mechanism for moving relatively the jaws of the gripping device constructed and arranged relatively to said means to be actuated to open the jaws upon the actuation of said means to connect the driving mechanism with the shaft, and to close the jaws upon the actuation of said means to disconnect the driving mechanism from the shaft. 7

' 8. A wax-thread sewing machine, having, in combination, stitch forming devices, a

' main shaft from which said devices are actuated, driving mechanism for theshaft,

vice comprising relatively movable'thread gripping jaws, and mechanism for moving relatively the jaws of the gripping device constructed and arranged relatively to said means to be actuated to open the jaws upon the actuation of said means to connect the driving mechanism with the shaft as the 'machine reaches itsfull normal speed.

tions for relatively actuating the jaws of the gripping device located relatively to the.

first treadle so that it is unaffected by the movement of the foot of the operator dur-;

ing the initial movement of the first treadle in a direction tofcause the connection of the driving mechanism with the shaft, and that it is actuated by the movement of the foot of the operator during the continued movement of the first treadle in the same dig rection.

r 10. A wax-thread sewing machine, hav

ing, in combination, stitch forming devices, a main shaft from which said devices are operated, a clutch for driving the shaft, a treadle for controlling the engagement and disengagement of the clutch, a thread gripping device comprising relatively movable thread gripping jaws, a second treadle and connections for relatively moving the thread gripping jaws arranged relatively to the first treadle so that the second treadle is unaffected by the movement of the foot of the operator during the movement of the first treadle to engage initiallythe members of the clutch, and that the second treadle is actuated to. open the thread gripping jaws by the continued movement of the foot of the operator in the same direction to engage firmly the members ofthe clutch.

11. A wax-thread sewingmachine, having in combination, stitch forming devices, a main shaft from which said devices are operated, driving mechanism for the shaft, a treadle and connections for controlling the connection of the driving mechanism with. and the disconnection of said mechanism from said shaft, a thread gripping device comprising relatively movable thread gripping jaws, and mechanism for relatively opening and closing the gripping jaws comprising a treadle arranged in juxtaposition relatively to the first treadle so that both treadles may be engaged at the same time by the foot of the operator.

FREDERIG E. BERTRAND. 

